NFL Draft 2012: Which Players Still Have Most to Prove After Combine?

For every Robert Griffin III, who seemed to answer every question NFL scouts had—height, weight, speed and football IQ—there seems to be five prospects that leave Indianapolis with more concerns surrounding them than they started with.

Luckily, these prospects have ample opportunities to confront these concerns before the NFL draft—private workouts, official visits or college pro days.

Stephen Hill (WR, Georgia Tech)

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A picture is worth a thousand words.

Stephen Hill vaulted himself into first-round discussions with his other-worldly combine performance, but as long as NFL receivers are still required to actually catch the ball, Hill still has some questions to answer.

Georgia Tech actually threw the ball a good bit this season, giving scouts ample time to see Hill's inconsistent hands and route-running. Hill will be a project, but few receiver prospects bring the potential that he can.

Mike Adams (OT, Ohio State)

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When watching Mike Adams on tape during the 2010 and 2011 NCAA seasons, you had to notice the fact that his strength seemed to improve, even though it was still not one of his strong points. So when Adams only was able to perform 19 bench press repetitions at the 2012 NFL Combine, some observers were not surprised

Nineteen reps isn't horrendous for a prospect with 34" arms, but combined with his tape it leads to some concerns. Scouts are going to need to ascertain whether Adams' technique—he can get a bit upright and lose his natural advantage—is to blame, or whether he will need some time in the weight room before being an impact player in the NFL.

Michael Brockers (DL, LSU)

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You can argue whether Brockers ran a 5.33 or a 5.08. You can ponder what his 7.46 3-cone time means. What you can't argue with is his relative lack of production during the 2011 NCAA season. Statistics rarely tell the whole picture, but when a defensive-line prospect in discussions for the Top 10 of the draft only is able to rack up two sacks, eyebrows tend to raise.

Brockers wasn't in on a ton of third-down plays for the LSU Tigers, so NFL teams will need to determine whether Brockers will only be a two-down player to start his career.

He certainly has the frame and potential to be an effective pass-rusher, but I think a move to 3-4 defensive end—where his run-stuffing will be appreciated and his lack of pass-rush blunted—would be his in his best interest.

Leonard Johnson (CB, Iowa State)

In the NFL, if a cornerback doesn't play fast, he won't be playing long. So when a cornerback runs a 4.65 at the combine like Johnson did, some NFL teams are going to have questions.

We scouted Johnson from the press box in Ames twice and have watched about 12 more of his games. Never once did we think he played like a "4.65 guy." Johnson's fluid hips, excellent body control and awareness allow him to play much faster between the lines.

While the 4.65 time might make some teams question Johnson's ability to press and run with receivers, he has shown that he can be physical enough to negate nearly any speed difference. Justin Blackmon, who we'll talk about in a moment, told me that Johnson was the "most physical cornerback" he had played that season.

Justin Blackmon (WR, Oklahoma State)

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Speaking of Blackmon, the former Oklahoma State receiver was poised to show in Indianapolis that he was the No. 1 receiver in the 2012 NFL draft.

Instead, he passed on the running and agility drills, opting instead to wait for his pro day in Stillwater. NFL scouts were left to wonder about Blackmon's speed while Michael Floyd (WR, Notre Dame) showed off his 4.42 40-yard dash.

To me, this shows that Blackmon's advisers are playing to the media—NFL teams know that Blackmon isn't as fast as Kendall Wright or Michael Floyd—not wanting the public perception of Blackmon as the top receiver to change.

If Blackmon would have run anywhere in between 4.5 and 4.65, NFL teams wouldn't have blinked—Blackmon's game isn't predicated only on speed. His body control, agility, blocking and hands make him a complete receiver.